1. Field of the Invention
The present invention relates to a rodless cylinder including a cylinder barrel, a piston housed in the cylinder barrel and a mounting table disposed on the external surface of the cylinder barrel, wherein the piston and the mounting table are connected to each other so that they can be moved together. More particularly, the present invention relates to a rodless cylinder equipped with a mechanism for supplying a pressure fluid to an external actuator mounted on the mounting table.
2. Description of the Related Art
In a rodless cylinder, generally, a piston is movably housed in a cylinder barrel, and a mounting table, which is disposed outside of the cylinder barrel, is connected to the piston so as to be able to move together therewith. The reason why such type of cylinder is called rodless cylinder is because no piston rod is connected to the piston thereof. The piston is reciprocated with the aid of the air supplied into the cylinder barrel, and the mounting table is reciprocated along the cylinder barrel following the movement of the piston. Accordingly, if an external actuator such as a chuck is mounted on the mounting table, various subassemblies can be transported between two arbitrary positions by operating the chuck interlocking with the movement of the piston.
In the conventional rodless cylinder, a mounting table 52 is provided on the external surface of a cylinder barrel 51, for example, as shown in FIG. 19. Various types of external actuators can be mounted on the mounting table 52. The external actuators include, for example, a chuck 55 for holding articles, a cylinder barrel 53 for reciprocating the chuck 55 along the axis Z and a braking device for applying a braking force to the piston housed in the rodless cylinder. In the conventional rodless cylinder described above, flexible pipes 54 are disposed, independent of the pipe for supplying air into the rodless cylinder, through which air is supplied from an air supply source to the external actuator.
However, the flexible pipes 54 must be disposed separately for the external actuator in the conventional rodless cylinder, so that the piping operation becomes troublesome. Moreover, since the flexible pipes 54 are flexed repeatedly following the movement of the mounting table 52, the parts in the air supply system including these pipes are worn rapidly, and these parts must be replaced soon. In addition, a wide installation space must be secured so as to prevents the flexible pipes 54 from interfering with the operators or the peripheral equipments.
The present invention has been proposed with a view to solving the above problems, and it is an object of the invention to provide a rodless cylinder which enables easy piping operation for the external actuator and which can prevent troubles attributable to the piping from occurring.